Thompson's "Kletva kralja Zvonimira" stands as a defining anthem of Yugoslav folk rock, blending traditional Serbian folk melodies with electric instrumentation to create a powerful sonic landscape. Released during the height of the genre's popularity in the 1970s, the track captures the raw energy and nationalist fervor characteristic of the era's music. The song's narrative centers on the legendary King Zvonimir, weaving a dramatic story that resonates deeply with audiences across the former Yugoslavia. Its enduring legacy lies in its ability to fuse historical storytelling with modern rock arrangements, establishing Thompson as a pivotal figure in the region's musical history and cementing the song as a cultural touchstone.